Claims
- 1. A magnetooptic head for recording/erasing information on/from a recording medium by irradiating the recording medium with a laser beam within a recording/erasing external magnetic field applied to the recording medium, which comprises:
- (a) a cylindrical condenser lens for focusing the beam on the recording medium;
- (b) a cylindrical hollow permanent magnet fixedly arranged outside said condenser lens coaxially therewith and magnetized radially from a center thereof to an outer circumferential surface thereof; for generating a recording/erasing external magnetic field and focusing actuator magnetic field in a radial direction of said condenser lens on the basis of an axial magnetic flux component thereof;
- (c) a cylindrical focusing coil arranged outside said cylindrical hollow permanent magnet coaxially therewith within the magnetic field generated by said cylindrical hollow permanent magnet for moving said condenser lens and said cylindrical hollow permanent magnets together in the axial direction of the recording medium to provide a focusing servo operation of the laser beam in cooperation with a radial magnetic component of said permanent magnet; and
- (d) an elastic member for movably supporting said condenser lens and said permanent magnet together relative to said focusing coil in the axial direction of said recording medium.
Priority Claims (3)
Number |
Date |
Country |
Kind |
61-175585 |
Jul 1986 |
JPX |
|
61-175586 |
Jul 1986 |
JPX |
|
62-29695 |
Feb 1987 |
JPX |
|
Parent Case Info
This application is a division of application Ser. No. 07/077,851, filed July 27, 1987 now U.S. Pat. No. 4,868,802.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4747668 |
Meyer et al. |
May 1988 |
|
4759005 |
Kasahara |
Jul 1988 |
|
Foreign Referenced Citations (2)
Number |
Date |
Country |
57-71529 |
May 1982 |
JPX |
61-96540 |
May 1986 |
JPX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
77851 |
Jul 1987 |
|